Cornell Stack

The new Cornell Stack provides an updated platform that combines the hosting services onto a single VM.

The service is intended for customers that have technical skills/knowledge in installing/maintaining web software. Customers that have limited technical knowledge/skills may be more comfortable with some of the options listed at: http://www.it.cornell.edu/services/hosting/

The Cornell Stack provides the following level of support: http://www.it.cornell.edu/services/hosting/support.cfm

Customers that require a higher level of customization and/or have a deep technical background may be more comfortable with a "Managed Server" and installing the web application stack on their own: http://www.it.cornell.edu/services/managed_servers/

What's new

A summary of the updated features:

• 64-bit RHEL 6 (Coldfusion can allocate more than 2 GB of memory)
  • CF9/LAMP currently using 32-bit RHEL5
• Coldfusion 10 using Java 1.7
  • CF9 currently using CF9 with Java 1.6
• PHP 5.4
  • LAMP2 currently uses PHP 5.3
  • PHP-FPM also now available as an alternative to mod_php (uses less memory)
• Python 2.7
  • No change from LAMP2
• Ruby 1.9.3
  • LAMP2 currently uses Ruby 1.8.7
• Perl 5.16
  • No change from LAMP2
• MySQL 5.5
  • Same version from LAMP2
  • MySQL database located on same VM versus separate
• Local storage
  • No longer uses NFS (Shared File Service) for storage
  • Customers can opt to continue to use SFS, but will incur additional charges
• Updated administrative tools
  • Can now modify both ".wdaccess" and ".htaccess" via web inteface
  • Can upload files via PHP Shell
  • Can utilize "pip" for installing Python software
• Shared Apache instance
  • Provides lower memory footprint for hosting multiple isolated instances

The PHP Shell/virtualenv utilities are no longer an "experimental" utility. There are some new "experimental" features that may be of interest for advanced web developers by special request.

• Git Repository
  • A git repository that can be used as an alternative to webdav for publishing code
• Mercurial Repository
  • A mercurial repository that can be used as an alternative to webdav for publishing code

What's Changed

Apache Web Server (httpd)

• The Apache version is now 2.2.15, some features from LAMP2/CF9 may not be available (i.e. FallbackResource)
• Many "default" configurations that existed in CF9 have been removed. Some examples:
  • Default "allow from all" for the "scripts","images","styles","icons" sub-folders
  • Default "allow from localhost" for the "tasks" sub-folder
• When using "PortalProxy" it may be necessary to update configurations
  • Previous configurations that used "localhost" may no longer work and need to be updated
• It is no longer possible to have "legacy" CU WebAuth configurations
  • This may require obtaining an SSL certificate and/or updates to ".htaccess" configuration files
• Change in ".htaccess" behavior (no longer inherit from "htdocs")
  • Previously in LAMP2/CF9 ".htaccess" files would be inherited up to the "htdocs" level when multiple sub-sites existed under once instance
  • This change can impact sites that make use of a large number of redirects/rewrite rules

Coldfusion 10

• Secure Profile enabled
  • Table of these listings can be found at: http://help.adobe.com/en_US/ColdFusion/10.0/Admin/WSf23b27ebc7b554b629cab0421369741d5a7-7fff.html
  • In a development setting you may want to remove the custom error templates to restore behavior similar to Coldfusion 9
• Oracle (tm) JDBC driver no-longer included
  • The Oracle driver from Adobe is provided, but customers may need to upload their own copy of the Oracle JDBC driver
• "Cornell" jar files for Fedora are no longer included

PHP-FPM 5.4

• When using PHP-FPM you will no longer be able to use a ".htaccess" file to manage PHP settings. Instead use a ".user.ini" file http://php.net/manual/en/configuration.file.per-user.php
• php_suhosin is no longer available

MySQL

• The mysql configuration has changed. Please use "localhost" instead of the previous hostname from LAMP2

File snapshots / restores

• You can no longer access file snapshots in the ".snapshot" directory. Instead you will need to use TSM to restore any files.

Details

Software Versions

Shared vs. Standalone Apache

In CF9/LAMP2 each "instance" represented a separate apache instance that could be started/stopped independently. This provides a high level of isolation, but can also consume more system resources and complicate server administration. The "shared" apache instance makes it possible to host a larger number of instances on a single apache instance while still providing isolation between the instances.

* Will start/stop ALL sites that are behind the shared Apache

How many instances

Using a VM with 2 GB of memory the following are some guidelines on possible deployments. Individual applications may vary (i.e. it's possible to have a single PHP/Python/Ruby/Perl application that consumes 100% of the memory. Increasing the amount of memory may make it possible to run more instances, but it is not a recommended best practice.

Please note that each instance could host anywhere from 1 website to 100 websites depending on how the software is configured (i.e. a single multisite drupal instance serving 100 websites).

Coldfusion

• 2 instances shared or standalone

PHP

• 3 standalone
• 9 shared

Python

• 3 standalone
• 9 shared

Ruby

• 3 standalone
• 9 shared

Static

• 3 standalone
• 100 shared

The estimates below are based on the following observed utilization